Abstract
Background: Dysfunction of the intestinal flora is an important factor in the occurrence and development of ulcerative colitis (UC). Chinese herb Huangqin decoction (HQD) can regulate intestinal flora in UC mice, yet its specific mechanism remains unclear. Our study aimed to clarify the mechanism of HQD in regulating intestinal flora of UC mice.Methods: 3%DSS - induced colitis mice were used to explore the pharmacodynamics of HQD. Colonic bacterial infiltration and the changes of intestinal flora were detected by FISH and 16SrDNA. Expression of RegⅢγ and PRRs (NOD2, TLR5, TLR4) were detected by FCM and WB, respectively. In addition, WB, SqPCR, or IHC were used for the expression of Nod2, MyD88, Rip2, and NF-κB p65 in colon. Cytokines were determined by ELISA.Results: HQD significantly restored the weight, the colonic length, and peripheral blood cell counts of colitis mice; reduced the DAI score and the histological score. 16SrDNA identification showed HQD regulated the balance of intestinal flora. Moreover, the expression of RegⅢγ was suppressed and colonic bacterial infiltration was prevented by HQD. Furthermore, the results of WB showed expression of NOD2 and TLR4 was inhibited by HQD, especially NOD2. And the data of WB, SqPCR and IHC explained that the NOD2-dependent pathway was inhibited by HQD.Conclusions: Our results reveal the mechanism of HQD(1g/kg) in regulating the intestinal flora of colitis mice, which may be closely characterized as the inhibition of the activation of Pattern Recognition Receptors (PRRs), especially NOD2.
Effect of Huangqin decoction on regulating intestinal flora in colitis mice characterized as inhibition of the NOD2-dependent pathway
